Alfonso Soriano went for an MRI on his left knee Saturday after having problems in the field on Friday. Soriano had been hoping to push the MRI back until after the weekend and will likely get a cortisone shot to relieve the pain if he doesn't have serious damage. "It's something that needed to be done, so the quicker the better," Cubs manager Lou Piniella told the Associated Press. If Soriano has a cortisone shot, Piniella claims that he could play by Tuesday.